1. The shell not only plays a role in protecting the internal structure but also serves as an important carrier for the appearance design of lighters. The materials of modern lighter shells are diverse, including metals, plastics, ceramics, etc. Metal shells, such as those made of zinc alloy and stainless steel, have a tough texture, good wear resistance and impact resistance. Plastic shells, with their advantages of rich colors, low cost and easy processing and molding, occupy a large share of the lighter market. Ceramic - shell lighters, with their unique texture and artistic sense, attract consumers who pursue individuality and quality.

2. As a practical tool in daily life, the progress of the design and production technology of lighters reflects the continuous development of industrial manufacturing levels. Ultrasonic welding technology, with its excellent performance in welding strength, sealing, appearance quality, production efficiency, environmental protection and safety, has become an indispensable key technology in lighter production. With the continuous progress of science and technology, it is believed that ultrasonic welding technology will be more widely applied and innovated in lighters and more fields, injecting new vitality into the improvement of product quality and the development of industrial production.